Pneumatic gauge and inflater mechanism



April 5', 1942.

H. W.,FOWLER PNEUMATIC GAUGE AND INFLATER MECHANISM Filed Oct. 31, 1938INVENTOR Harv/0 1M. f'ow/er' Patented Apr. 7, 1942 l PNEUMATIQGAUGE AND:INFLATER- MECHANISM naroiawzrowier, Oakland, Calif.

Application ctober3l, 1938; Serial No. 237,814

1 Claim.

1 The invention relates toa pneumaticgauge'and inflator mechanism suchas commonly used in gasoline service or filling stations garages and thelike for filling and gauging pneumatic tires.

It. is customary, to construct. arisinflator of the character describedof a unitary body containing both a gauge mechanism and an air'inflatorvalve and to so fashionthe body that the samewill comfortably fit thehand of the user so that the valve may be conveniently and readilyoperated to either fill the tire orconnect the tire to the gauge forreading the pressure of the chin the tire.

The iniiator device is usually equipped with a. relatively short,'flexible discharge conduit which is equipped at the discharge endthereof with a chuck for engaging the valve stem of. .the tire. 'Theinflator body is adapted for connection to a longer flexible conduitleading to a source of air under pressure By so fashioning the inflatormechanism, it is convenient for the operator to hold the inflator bodyin one hand and operate'the valve mechanism withthe thumb orfingers ofthe same hand, While having .the other hand free for applying the chuckto the tire valve stem.

prevent. relative rotation of the gauge piston and the gauge cylinder.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth in the followingdescription of the preferred form of the invention which is illustratedin the drawing accompanying and forming part of the specification. It isto be understood, however, that variations in the showing made by thesaid drawing and description may be adopted within the scope of theinvention as set forth in the claim.

Referring to said drawing:

Figure 1 is a longitudinal sectional viewof a pneumatic gauge andinflator mechanism constructed in accordance with the present invention.

Figure 2 is a cross-sectional view taken sub- ;stantially on the planeof line 2-2 of Figure 1.

Figure 3 is a side elevation shown partly in section of a part of thegauge mechanism.

Figure 4 .is. a cross-sectional view of the tire valve engaging chuck.

Figure 5 is an end elevation of another part of the gauge mechanism.

With reference more specifically to the acagainst the seat 26. themember 2d and extending longitudinally companying drawing, thepneumatic. gaugesand infiator mechanism'of the present inventioncomprises .a body having an elongated portion' lz formed with a'longitudinalmbore l3 therein extending from one end Idof said portionto adjacent an oppositeend 16 thereof. Joined'to the longitudinalportion I! at the end 15 thereof is a transversely extending portion ll,which is formed with. a bore- It therethrough and inlet and dischargepassages l 9 and 2! adapted for connectionto aisource of air underpressure and to an object to be inflated respectively. The body is alsoprovided. with a passageZZ connecting the bore it to the adjacent end 23of .the bore iii.

'In: accordance with the present construction,

sthe'elongated-portion l2 forms a housing for a pneumatic gauge whilethe transverse portion ll .fOI'll'lS a housing fora valve mechanism forselectively connecting the discharge passage 2| to the inlet passage i9or to the gauge passage 22 for gauging the air pressure of a tire or thelike when the chuck is applied thereto, or for venting the gauge passage22 to the atmosphere, when the chuck is not so applied. The valvemechanism here shown consists of a valve supporting member 24 mounted inthe bore l3 and which is formed with a seat 26 intermediate the passagesl9 and 2| for receipt of a valve 2i, which is normally urged by a spring23 to a seated position Carried centrally through through the bore I8 isa hollow tubular valve stem 29, which is centered intermediate itslength and above the passage 2! by a spool 35 and is formed. adjacentits upper end with an enlarge- ;ment32slidably mounted within the spcoland having an upwardly projecting portion The stem is normally elevatedfrom the valve 2! by means of .a" spring. 3 8 compressed in-the'interior of. the spool 3| and engaged under the enlargement .32. Amanually operated button 36 having a shaft portion 37 extended through acap 38 closing the upper end of bore it is depressed against the stem 25to unseat the valve 27.

-When the valve is so unseated, air may pass from the inlet passage :19around the valve and around the 'stem 25 to the 'dischargepassage 2|.Upon release of the button 3%, the valve it will eturn to its normalseated. position under the influence of the applied air pressure and thespring 28, and

:the'stem 29 will be lifted from the valve by spring 34. .The air maythen return from the tire by Way of passage 2|, then. around the valvestem to the base thereof and up through a center passage therein toaside. vent 39, where the air is liberated intothe interior. of the spool3| and passes out through a side passage All in the spool, which is inregistration with passage 22 to the gauge mechanism. Upon disconnectionof the discharge passage 2| to the tire, the air in the gauge bore willbe released back through this passage to the atmosphere. Also, where thevalve stem is again depressed after gauging of the air pressure, theportion 33 of the valve stem is so mounted as to allow the venting ofair around the stem when the latter is depressed.

The discharge passage 2| is here shown connected by means of a conduit42 to a chuck 43 for connection of the discharge opening to a tire valvestem or the like. The chuck 43 is provided with a movable center piece Hwhich is adapted to engage and displace the tire valve stem and is heldto a limited movement by transverse shoulders 12 which are appropriatelyspaced from each other to allow the free passage of air through thechuck for inflating the tire when applied to the tire valve stem and forventing the discharge passage to the atmosphere when removed from thetire valve stem.

One of the principal features of the present invention and ashereinbefore noted, is the construction of the gauge mechanism hereused. In the present form of gauge, a gauge piston 44 of generallycylindrical form is reciprocally mounted in the bore l3 and if desiredand as here shown, a bearing tube 46 may be interposed between thepiston and the bore side wall. The gauge piston is here in the form ofan elongated cylinder having a closed end 41 sealed in the tube 46 bymeans of a packing washer 48 adjacent the air inlet end of the bore, soas to render the movement of the gauge piston responsive to the pressureof air entering the bore. The movement of the piston is resilientlyresisted by a pair of helical springs 49 and mounted one within theother and extending longitudinally through the bore l3 from the closedend 41 of the piston to a closure 52 at the end M of the gauge body. Theclosure 52 is so formed as to normally engage one end 53 of spring 5| sothat the initial movement of the gauge piston is resisted by spring 5|and is recessed so as to engage the end 54 of spring 49 only after thegauge piston has been moved a portion of its gauging distance, so thatfor the remainder of the distance of movement of the gauge piston, thesame is resisted by both springs 49 and 5i to decrease the increment ofmovement for a corresponding increase of pressure.

The gauge piston is provided with a plurality of longitudinalcalibrations 54 which are aligned longitudinally for passage by alignedgauge sight openings 56 and 5! in the tube 46 and gauge body l2.Preferably, a transparent closure 58 is mounted in the sight opening 51for sealing the gauge bore. In accordance with the present inventionmeans is provided for preventing a relative rotational displacement ofthe gauge piston in the bore and for holding the calibrations inlongitudinal alignment with the sight opening. In the presentconstruction such means is considerably simplified fromthat heretoforeused and consists simply in a longitudinal guide on one of the membersand a pin engaging the guide on the other member. As here shown, thelongitudinal guide is provided on the gauge piston in the form of anelongated slot 59 and the pin is carried by the wall of the gauge bodyI2, and is here in the form of a screw 6| threaded through the body walland having the inner end 62 thereof extended through the tube 46 andengaged in the slot 59. The outer end of the screw is formed with aconventional slotted head 63 so as to facilitate retraction of the screwfrom the slot in the gauge piston when necessary, for dismembering ofthe gauge. The slot 59 in the gauge piston preferably extends forsubstantially the full length of the piston, as indicated in Figure 1,and opens to the open end 64 of the skirt of the gauge piston andextends longitudinally therefrom to the closed end 41 of the piston.

In order to prevent unauthorized tampering with the gauge mechanism andalso to prevent accidental release of the screw 6|, I preferablyassociate the discharge conduit 42 in such relation to the gauge body asto cover and conceal the screw head 63. As here shown, the conduit 42 isconnected by means of a fitting 66 to the discharge passage 2| andextends longitudinally therefrom in parallel relation to the elongatedgauge body portion l2, and is supported adjacent the end l4 of the gaugebody by means of a ringlike conduit support 61, here formed integrallywith the gauge body. In accordance with the present construction thescrew 63 and the discharge passage 2| and the conduit support 61 are allarranged in a substantially common transverse plane, so that the conduitwill extend directly across the head of the screw in spaced opposedposition thereto, thereby preventing an accidental removal of the screwor unauthorized access thereto.

While I have shown the guide pin mounted on the stationary part and thelongitudinal guide slot on the movable part, and for the reasons abovepointed out prefer such construction, I may nevertheless reverse theguide parts so as to place the longitudinal guide slot on the stationarywall of the cylinder of the gauge body and the guide pin on the gaugepiston. Also, as will be understood, a plurality of such guide slots andpins may be used at circumferentially spaced portions of the piston andcylinder if desired.

I claim:

In a device of the character described a body composed of an elongatedportion and a lateral offset portion at one end of said elongatedportion and being formed with a longitudinal bore in said elongatedportion and with an air discharge passage in said lateral portionopening to a side thereof adjacent saidtelongated portion and having theaxis thereof at said side substantially parallel to said elongatedportion, an elongated gauge piston reciprocally mounted in said bore,means for preventing relative rotation of said piston in said bore andincluding a longitudinal slot in said piston and a screw threadedthrough the wall of said elongated body portion with the head of saidscrew at the outside of said body and the opposite end of said screwprojecting into said bore and engaging in said slot, the axis of saidscrew being at substantially right angles to and substantiallyintersecting the axis of said air discharge passage, a conduit connectedto said air discharge passage and adapted for connection to a tire orother object to be infiated, and means attached to the elongated portionof the body supporting said conduit substantially axially of saiddischarge passage whereby the said conduit is mounted across and coversthe head of said screw.

HAROLD W. FOWLER.

